Work-handling mechanism for machine tools



March 27, 1956 A. s. DINSMORE ET AL 2,739,717

WORK-HANDLING MECHANISM FOR MACHINE TOOLS Filed April 15, 1953 2 Sheets-Sheet 1 Fig. l

INVENTOR.

EDWIN R. SMITH.

fgm rw ARTHUR S. DINSMORE.

March 27, 1956 A. S. DINSMORE ETAL 2,739,717

WORK-HANDLING MECHANISM FOR MACHINE TOOLS Filed April 15, 1953 2 Sheets-Sheet 2 IN V ENTOR.

EDWIN R. SMITH.

ATTY;

ARTH UR S. DINSMORE.

Unite WORK-HANDLING MECHANISM FOR MACHINE TOOLS Application April 15, 1953, Serial No. 348,888

1 Claim. (Cl. 2141} This invention relates to mechanism for automatically inserting and removing workpieces from a machine tool, such as a lathe or grinding machine.

It is the general object of our invention to provide work-handling mechanism so constructed that the working area of the machine tool is substantially unobstructed during the working cycle, and so constructed that the finished workpieces are deposited and new workpieces are supplied to the loading unit at a point remote from the working area.

More specifically, we disclose a swinging support for the work-handling mechanism by which such mechanism may be swung rearward for deposit and replenishment of workpieces during the working cycle of the machine tool.

Our invention further relates to arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claim.

A preferred form of the invention is shown in the drawings, in which:

Fig. 1 is a front elevation of an engine lathe having our improved work-handling mechanism associated therewith;

Fig. 2 is a plan view, looking in the direction of the arrow 2 in Fig. 1; and

Fig. 3 is a partial rear view, looking in the direction of the arrow 3 in Fig. 2.

Referring to the drawings, we have shown our invention associated with an engine lathe having a frame F, a head-stock H, a tail-stock T, a live center 10 and a dead center 11, and on which centers 21 piece of work W is rotatably supported. The live center 10 may be replaced by a suitable chuck of any usual construction if desired.

The work-handling mechanism comprises alternativelyoperating front and rear units of the type shown in our prior application, Serial No. 300,708, filed July 24, 1952, now Patent No. 2,714,324. The front unit is clearly shown in Fig. 1 and the rear unit is of substantially identical construction.

Both units are mounted on the converging front and rear faces of an arm or support 20 which is pivotally mounted on a fixed upright post or standard 22. A reversible motor M is mounted on the swinging arm 20 and is connected to rotate a gear 30 in a gear box 31 which is also secured to the arm 20. The gear 30 meshes with a similar gear 32 which is secured in fixed position to the upper end of the post 22.

As the gear 32 is fixed, rotation of the gear 30 will cause the arm 20 to swing about the axis of the post 22 from the full-line or operative position shown in Fig. 2 to the depositing and replenishing position shown in Fig. 3.

Each loading or unloading unit comprises grippers 40, or 40a (Figs. 1 and 3) mounted on a three-armed lever States Patent 41 (Fig. 1) which is pivoted at 42 to a slide 43. The slide 43 is movable downward along an inclined path in guideways 44 fixed on the arm 20.

As the slide 43 is moved downward, the lever 41 is rocked on its pivot 42 by the action of fixed cams, as 45 and 46, and in such manner that the grippers 40 adjacent the head stock H are lowered more rapidly than the grippers 40 adjacent the tail-stock during the first part of the downward movement of the slide 43. The work is thus lowered with a plunging or diving motion which facilitates insertion of the head end of the work under overhanging structure.

For a more complete disclosure and full description of this loading unit and its operation, reference is made to our prior application above identified.

The corresponding mechanism at the back of the arm 20 is similarly constructed and the grippers 40a are operative to grasp and remove a piece of finished work from the centers 10 and 1.1. The arm 20 is then swung to the position shown in Fig. 3, where the finished workpiece W2 is deposited on a suitable discharge structure 50, and where a new workpiece W3 on a supply stand 51 is grasped by the grippers 40 of the front loading unit.

These operations all take place while the arm 20 is swung rearward and during the performance of the working cycle on the workpiece then in the lathe.

With this construction, no time is lost in depositing and discharging a finished workpiece, nor in replenishing the front loading unit. Removal of the finished workpiece and replacement thereof may take place immediately after completion of the operations of the machine tool thereon.

The coordinating mechanism for these successive movements may be of the general type disclosed in our prior application and operates to remove and replace a finished workpiece and to thereafter swing the arm 20 rearward and to deposit the finished workpiece and grasp a new workpiece while in such rearward position. The arm 20 may then be returned to operative position as the working cycle is completed.

Having thus described our invention and the advantages thereof, we do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claim, but what we claim is:

Work-handling mechanism for a machine tool comprising an arm having a portion of V-shaped cross section, a fixed upright support on which one end of said arm is pivoted, loading and unloading units mounted on the side faces of the V-shaped portion of said arm and movable to operative position along separate paths converging on the work axis, and means to swing said arm and units angularly rearward from a forward loading and unloading position to a rearward discharge and replenishing position, and the means for swinging said arm comprising a reversible motor mounted on said arm, a gear mounted on said arm eccentric with respect to the pivotal support of said arm and rotatable by said motor, and a second gear fixed on said support and axially aligned therewith and engaged by said first gear to swing said arm between forward and rearward positions.

References Cited in the file of this patent UNITED STATES PATENTS 1,252,935 Norquest Jan. 8, 1918 1,794,424 Smith et a1 Mar. 3, 1931 1,933,225 Smith Oct. 31, 1933 2,198,976 Rober Apr. 30, 1940 Patented Mar. 27, 1956 

